Hinge angle detection
Particular embodiments described herein provide for an electronic device that includes a first housing, where the first housing includes at least one first housing accelerometer and at least one first housing gyroscope, a second housing, where the second housing includes at least one second housing accelerometer and at least one second housing gyroscope, and a hinge. The hinge rotatably couples the first housing to the second housing, where a hinge angle is determined using data from the first housing accelerometer, the second housing accelerometer, the first housing gyroscope, and the second housing gyroscope if the electronic device is not in a portrait orientation where the hinge is vertical to a ground or not in motion and is determined using data from the first housing gyroscope and the second housing gyroscope if the electronic device is in portrait orientation or is in motion.
1. An electronic device comprising:
a first housing, wherein the first housing includes a first housing display, at least one first housing accelerometer, and at least one first housing gyroscope;
a second housing, wherein the second housing includes a second housing display, at least one second housing accelerometer, and at least one second housing gyroscope; and
a hinge, wherein the hinge rotatably couples the first housing to the second housing and the first housing accelerometer, the first housing gyroscope, the second housing accelerometer, and the second housing gyroscope are all located near the hinge of the electronic device, wherein, if the electronic device is not in a portrait orientation where the hinge is vertical to a ground or is not in motion, a hinge angle is determined by subtracting an angle of the second housing relative to a horizontal plane from an angle of the first housing relative to the horizontal plane, wherein the angle of the first housing relative to the horizontal plane is determined using data from the first housing accelerometer and the angle of the second housing relative to the horizontal plane is determined using data from the second housing accelerometer.
2. The electronic device of claim 1 , wherein the hinge angle is determined using data from the first housing gyroscope and the second housing gyroscope, but not from the first housing accelerometer or the second housing accelerometer if the electronic device is in the portrait orientation or is in motion.
3. The electronic device of claim 1 , wherein the hinge angle is determined using state transition data.
4. The electronic device of claim 3 , further comprising:
a state transition engine, wherein the state transition engine is used to determine the state transition data based on angular velocity data from the first housing gyroscope and the second housing gyroscope.
5. The electronic device of claim 3 , further comprising:
a state transition engine, wherein the state transition engine is used to determine the state transition data based on angular velocity data from the first housing gyroscope and the second housing gyroscope, wherein the hinge angle determined using the state transition data is corrected using data from the first housing accelerometer and the second housing accelerometer.
6. The electronic device of claim 1 , wherein a Kalman filter to determine the hinge angle.
7. The electronic device of claim 1 , wherein the first housing can rotate about three hundred and sixty degrees relative to the second housing.
8. The electronic device of claim 1 , wherein an image on a display is changed based on the determined hinge angle.
9. The electronic device of claim 1 , wherein an angle of the first housing and the horizontal plane is determined by atan 2(a 1z /a 1y )+π/2, where a 1z is a component of gravity on a Z axis of the first housing accelerometer and a 1y is the component of gravity on a Y axis of the first housing accelerometer.
10. A method comprising:
determining that a first housing of an electronic device is rotated relative to a second housing of the electronic device about a hinge that rotatably couples the first housing to the second housing, wherein the first housing includes a first housing display, at least one first housing accelerometer, and at least one first housing gyroscope and the second housing includes a second housing display, at least one second housing accelerometer, and at least one second housing gyroscope;
determining an angle of the first housing relative to a horizontal plane using data from the first housing accelerometer;
determining an angle of the second housing relative to the horizontal plane using data from the second housing accelerometer;
determining angular velocity data from the at least one first housing gyroscope and the at least one second housing gyroscope;
determining a hinge angle based on the angular velocity data from the at least one first housing gyroscope and the at least one second housing gyroscope if the electronic device is in a portrait orientation where the hinge is vertical to a ground or is in motion; and
determining the hinge angle by subtracting the angle of the second housing relative to a horizontal plane from the angle of the first housing relative to the horizontal plane, if the electronic device is not in the portrait orientation where the hinge is vertical to a ground or is not in motion.
11. The method of claim 10 , further comprising:
determining the hinge angle using state transition data.
12. The method of claim 11 , further comprising:
determining the state transition data based on angular velocity data from a first housing gyroscope and a second housing gyroscope and a previously determined hinge angle.
13. The method of claim 10 , wherein a Kalman filter is used to determine the hinge angle.
14. The method of claim 10 , wherein the first housing can rotate about three hundred and sixty degrees relative to the second housing.
15. The method of claim 14 , further comprising:
changing an image on the first housing display in the first housing based on the determined hinge angle.
16. A system for determining a hinge angle, the system comprising:
a first housing, wherein the first housing includes a first housing display, at least one first housing accelerometer and at least one first housing gyroscope;
a second housing, wherein the second housing includes a second housing display, at least one second housing accelerometer and at least one second housing gyroscope;
a state transition engine, wherein the state transition engine is configured to determine state transition data; and
a hinge, wherein the hinge rotatably couples the first housing to the second housing, wherein if the system is not in a portrait orientation where the hinge is vertical to a ground or is not in motion, a hinge angle is determined by subtracting an angle of the second housing relative to a horizontal plane from an angle of the first housing relative to the horizontal plane, wherein the angle of the first housing relative to the horizontal plane is determined using data from the first housing accelerometer and the angle of the second housing relative to the horizontal plane is determined using data from the second housing accelerometer and the hinge angle is determined using data from the state transition data if the system is in the portrait orientation where the hinge is vertical to a ground or is in motion.
17. The system of claim 16 , wherein the state transition engine determines the state transition data based on angular velocity data from the first housing gyroscope and the second housing gyroscope and a previously determined hinge angle.
18. The system of claim 16 , wherein a Kalman filter is used to determine the hinge angle.
19. The system of claim 16 , wherein the first housing can rotate about three hundred and sixty degrees relative to the second housing.